"You'll need a new app to open this file" is probably the most common error faced by millions of Windows users every day. This is either because the program required to open a file is not available on your system or there may be other issues.

What is .F4V file extension?

Video container format used by Adobe Flash; based on the ISO MP4 format, which is based on the Apple QuickTime container format; specified by ISO/IEC 14496-12 as a base media file format; supported by Flash Player Update 3 (9,0,115,0) and higher.
F4V files are similar to .FLV files, but use "boxes" to store data. Examples of boxes supported by the F4V format are the ftyp box (player requirements), the moov box (file header), the mvhd box (playback information), the trak box (media tracks), the uda box (free-form user data), the meta box (metadata), and several others.
You can see a list of software programs here on easyfileopener.org that can open this file type so that you don’t need to search for it on the web. You can then open your file with this extension using a software listed below.